A multiplicity of medical instruments are handled in clinical procedures. By way of example, in the context of a surgical operation, the instruments required to this end must be provided, checked and routed to disposal or preparation after use. To this end, it was found to be useful to provide the medical instruments with a marker which facilitates identification and tracking. Here, machine reading of the marker is desirable for the purposes of increasing the efficiency and safety of the procedures.
The practice of providing medical instruments with one-dimensional codes (line code, barcode) or two-dimensional codes, for example matrix codes, which may be read by appropriate optical readers is known. This reading process is however subject to a multiplicity of influences which reduce the reliability of reading. For example, barcodes applied to surgical instruments by means of a laser have often already faded after approximately half a year's use within the scope of operations and are only readable with difficulty or no longer readable at all. Mechanically applied codes lead to the onset of rusting and are subject to similar deterioration.
Furthermore, the use of radiofrequency identification transponders, which are also referred to as RFID transponders or RFID tags, for marking medical instruments, in particular surgical instruments, is known. The RFID tag contains a memory which stores identification data of the instrument, such as a series number, which may be read by means of an electronic reader. However, the available installation space for the integration of an RFID tag into the instrument is tightly delimited in many surgical instruments, particularly in the case of endoscopic instruments. Furthermore, the reading range of the RFID tags, which are usually tuned to the RF (radio frequency) range with an operating frequency of 13.56 MHz and which have a miniaturized structure, is only a few millimeters. Therefore, it is necessary to place the reading head of the reader as closely as possible to the RFID tag for a reliable data transfer. Therefore, the RFID tags of medical or surgical instruments are generally freely accessible and visible from the outside in order to facilitate a correspondingly close approach of the reading head. However, such an RFID transponder arranged on the surface may be mechanically disturbing, or at least be perceived as disturbing, when handling the instrument and may possibly generate surface roughness which makes cleaning the instrument more difficult. Furthermore, such an arrangement of the RFID tag is connected with great manufacturing outlay.
DE 197 23 442 A1 has disclosed an endoscope with a registration device arranged in the endoscope interior, said registration device capturing at least one ambient parameter to which the endoscope is exposed, wherein the information registered by the registration device may be queried from the outside. Together with the stored data, the registration device is able to transfer a unique identification of the endoscope.
In accordance with DE 200 12 237 U1, a transponder in the case of an endoscope is embedded swimming in a recess in the outer surface of the housing of the endoscope. DE 10 2011 052 501 A1 proposes an RFID tag for equipping surgical instruments, said RFID tag comprising a metal frame and an RFID element with an antenna which, spatially, is arranged substantially outside of the metal frame. In accordance with US 2014/0210977 A1, an endoscope system is embodied for wireless transfer of energy and data, wherein an endoscope and a camera head which is couplable to the endoscope each have a transponder/transceiver. Both transponders/transceivers are configured for wireless transmission and reception of signals from one another.
US 2004/0092991 A1 has disclosed a surgical tool system comprising a handpiece and a cutting accessory, wherein an RFID chip is arranged at an inner wall of an external hub of the cutting accessory. The RFID chip is assembled on a small flexible circuit carrying a conductor track forming a coil. A further coil is housed in the handpiece and serves to read and write data into the RFID chip.
EP 2 210 219 B1 has disclosed an RFID tag which may be used in medical applications and has a hermetically sealed and sterilizable embodiment. The RFID tag comprises a printed circuit board assembly comprising a printed circuit board, an RFID circuit, an antenna and a metallic ground plate, wherein the printed circuit board has a first side and a. second side, the printed circuit board carrying the antenna on its first side and the ground plate on its second side and the RFID circuit being coupled to the antenna and the ground plate. The RFID tag further comprises a formed-over housing, which surrounds the printed circuit board assembly and hermetically seals the latter, the housing consisting of a material which is sterilizable and has a dielectric constant between approximately 1 and 5. The antenna may have a folded configuration with a central part extending from the RFID circuit to one end of the printed circuit board and with a pair of oppositely directed arms.
The non-generic WO 2006/080615 A1 has disclosed an eyelet comprising an eyelet base made out of a conductive material, which comprises a ring part attached tightly to an object and a fastening part. The eyelet further comprises an RFID circuit module, which is assembled at the eyelet base in order to use the eyelet base as an antenna. A slot is formed in the eyelet base and the RFID circuit module is electrically connected to parts which are defined by the slot. The likewise non-generic document US 2010/0007501 A1 describes a container, which may be used for receiving medical products and which has a circular RFID tag.